Australia's Department of Primary Industries and Development (DPIRD) has found that strategic orchard thinning can help ensure more consistent avocado supplies.

The research was part of the six-year Avocado Industry Capacity Building project, co-funded by DPIRD and Hort Innovation Australia, to support the fledging industry’s development.

The three-year DPIRD trial at a Manjimup commercial avocado property tested three thinning alternatives, which reduced fruit inconsistency through strategic and quantified crop manipulation.

DPIRD research scientist Declan McCauley said fruit thinning significantly reduced the alternate bearing of Hass avocados. 

“The orchard was thinned roughly one month after fruit set at three different rates based on the number of fruit per inflorescence – the cluster of flowers arranged on a stem," he explained. "Thinning was undertaken at rates of one, two and three fruits per inflorescence and compared with an unthinned control."

He explained that when thinning, results showed that there were fewer trees with alternate and irregular bearing with the one fruit per inflorescence treatment – especially when compared to the control. 

"This resulted in more stable yields of avocados over the trial period,” he added.

Quality was not affected by the process. Tree growth and mineral status did not change between treatments. 

Findings are now being shared with Western Australian agricultural industry and interstate to inform orchard management strategies.

The Avocado Industry Capacity Building project also delivered an early disease detection technique to assist growers to manage risks to orchards.

The government of Western Australia reports that avocado volumes are expected to grow as much as one-third once Australia's orchards mature in the next few years. While annual production fluctuates significantly, an average of about 40,000 tonnes of Western Australian avocados are produced each year, worth more than $200 million.